After both World War I and World War II, there was a consensus that wartime aerial reconnaissance would prove indispensible for urban and rural planners in their peacetime rebuilding, and books of aerial photographs became standard texts in schools of planning. However, it can be questioned whether aerial views changed perceptions, or whether they confirmed already accepted opinions. What we see is determined to some extent by what we know, and it takes time before a new means of viewing the world informs what we know to the extent that we see differently. Davide Deriu, in his article in this issue, shows how the same aerial image could be used in different contexts, and it would seem that it took time before aerial vision came to be appreciated for what it could contribute to our understanding of the terrestrial domain. This did not, however, stop aerial photographs being used as evidence of urban blight, and confirmation of planning orthodoxy, when they might have provided an opportunity of seeing the world anew. This article looks at post-World War II planning in London, particularly the County of London Plan and the Greater London Plan, and asks what aerial photography contributed to both of these plans, and how it informed the postwar planning of the metropolis.